As shown in FIG. 1, a mobile communication system standardized by the 3GPP (3rd Generation Partnership Project) is configured as follows. Specifically, a radio base station NodeB (transmitter apparatus) is configured to transmit a DCCH (Dedicated Control Channel), a DTCH (Dedicated Traffic Channel), a CCCH (Common Control Channel) and the like, to a mobile station UE (receiver apparatus) in downlink.
On the other hand, in uplink, the mobile station UE (transmitter apparatus) is configured to transmit a DCCH, a DTCH, a CCCH and the like, to the radio base station NodeB (receiver apparatus).
Moreover, as a logical channel for MBMS (Multimedia Broadcast and Multicast Service) standardized by the 3GPP, the radio base station NodeB (transmitter apparatus) is configured to transmit an MTCH (MBMS Traffic Channel) and an MCCH (MBMS Control Channel) to the mobile station UE (receiver apparatus) in downlink.
In addition, in downlink, as a physical channel for the HSDPA (High Speed Downlink Packet Access) that is the downlink high speed packet communication standard defined by the 3GPP, the radio base station NodeB (transmitter apparatus) is configured to transmit an HS-SCCH (High Speed Shared Control Channel), an HS-PDSCH (High Speed Physical Downlink Shared Channel) and the like, to the mobile station UE (receiver).
Additionally, in the HSDPA, the radio base station NodeB (transmitter apparatus) is configured to generate an MAC-hs PDU in the MAC-hs layer by multiplexing MAC-d PDUs (Protocol Data Units) received from the MAC-d layer, and to transmit the generated MAC-hs PDU by using the HS-DSCH (High Speed Downlink Shared Channel) associated with the HS-PDSCH.
Here, the MAC-d PDUs multiplexed into the MAC-hs PDU are in a fixed size for each MAC-d flow. As shown in FIG. 10, an MAC header is added to the MAC-hs PDU in the MAC-hs layer of the radio base station NodeB (transmitter apparatus), the MAC header including an “SID (Size Index Identifier)” indicative of the size of an MAC-d PDU for each MAC-d flow, and “N (Number of MAC-d PDUs)” indicative of the number of the MAC-d PDUs.
The conventional HSDPA, however, does not allow an MAC-hs header to include identification information for identifying information elements (for example, an MAC control block and the like) other than the MAC-d PDU, and to include size information indicating the respective sizes of these information elements. Thus, the conventional HSDPA has a problem that information elements with variable sizes, other than the MAC-d PDU, cannot be multiplexed into the MAC-hs PDU.
Non-Patent Document 1: 3GPP TS 25.321 v7.0.0